Intermaxillary fixation is performed in order to keep a jawbone immobile and in a correct position when orthodontic surgery is carried out for a maxillary fracture repositioning, jaw deformities, and the like. Intermaxillary fixation is carried out by fixing the upper and lower jaws using a metal wire or another ligature wire. Intermaxillary fixation is preferably performed as soon as possible following injury or surgery. However, there are cases in which the respiratory tract becomes blocked by vomiting, hemorrhaging, intraoral swelling, or the like following injury. When the respiratory tract is blocked, oxygen deficiency may cause irreversible brain damage in four to six minutes and there is danger of death when such a state remains unresolved for 10 to 15 minutes or longer. Therefore, the respiratory tract must be cleared immediately. Since a patient with intermaxillary fixation cannot open the mouth, the intermaxillary fixation must be rapidly released and the respiratory tract cleared.
The intermaxillary fixation is released by cutting the ligature wire fixing the upper and lower jaws using wire-cutting scissors or the like. However, medical personnel are not necessarily near a patient with a blocked respiratory tract, and the respiratory tract must be cleared in a very short period of time. It is therefore preferred that the intermaxillary fixation be released by a person in the vicinity. However, there is a problem in that it is very unlikely that the intermaxillary fixation can be released using wire-cutting scissors or another tool when a person who does not have any knowledge of intermaxillary fixation removal encounters a patient with a blocked respiratory tract.
In view of the above, various devices for releasing intermaxillary fixation have conventionally been proposed in order to rapidly release intermaxillary fixation without a tool even if the person does not have knowledge about releasing intermaxillary fixation.
In Prior Art 1, an arch wire is mounted on the upper and lower jaws, a hook is provided so as to straddle the arch wire, and the upper and lower jawbones are fixed. The hook is formed using a hard metal wire. A holding part is formed on the hook and the intermaxillary fixation is released by pulling the holding part outward from the mouth (e.g., see non-patent document 1).
In Prior Art 2, first, ordinary intramaxillary fixation is performed in the upper and lower jaws. A gap is formed in the vertical direction between the surface of the teeth and intramaxillary fixation means. A loop is formed by passing through the gap a ligature wire that is disposed between the upper and lower jaws, and an interlocking unit is passed through the loop. The interlocking unit is a metal wire having a thickness that prevents passage through the gap. Intermaxillary fixation can be set by applying tension to the ligature wire in order to hold the interlocking unit in place. In the case that the intermaxillary fixation is to be released, the holding part formed on the interlocking unit is pulled outward from the mouth, whereby the interlocking unit moves along the row of teeth, the interlocking unit is sequentially released from the ligature wire loop, and the intermaxillary fixation is released (e.g., see non-patent document 2).
Non-patent Document 1: Yasoo Watanabe et al., “Removable Device for Intermaxillary Fixation Following Orthodontic Surgery,” The Japanese Journal of Orthodontics, 1985, V44, p. 160-164.
Non-patent Document 2: Kazuhiko Tamari et al., “Instantly Releasable Device for Intermaxillary Fixation Following Orthodontic Surgery and Jawbone Fracture Repositioning,” The Japanese Journal of Orthodontics, 1988, V47, p. 811-814.